title: Estimated incidence of erythema migrans in five regions of France and ecological correlations with environmental characteristics.
abstract: BACKGROUND
  While several studies conducted on Lyme borreliosis (LB) risk in the United States showed an association with environmental characteristics, most of European studies considered solely the effect of climate characteristics.
  
  
  OBJECTIVE
  The aims of this study were to estimate incidence of erythema migrans (EM) in five regions of France and to analyze associations with several environmental characteristics of the place of residence.
  
  
  METHODS
  LB surveillance networks of general practitioners (GPs) were set up for a period of 2 years in five regions of France. Participating GPs reported all patients with EM during the study period. Data were pooled according to a standardized EM case definition. For each area with a participating GP, age-standardized incidence rates and ratios were estimated. Associations with altitude, indicators of landscape composition, and indicators of landscape configuration were tested with multivariate Poisson regression.
  
  
  RESULTS
  Standardized estimated incidence rates of EM per 10(5) person-years were 8.8 [95% confidence interval (CI)=7.9-9.7] in Aquitaine, 40.0 (95% CI 36.4-43.6) in Limousin, 76.0 (95% CI 72.9-79.1) in the three participating départements of Rhône-Alpes, 46.1 (95% CI 43.0-49.2) in Franche-Comté, and 87.7 (95% CI 84.6-90.8) in Alsace. In multivariate analysis, age-adjusted incidence rates increased with the altitude (p<0.0001) and decreased with forest patch density (p<0.0001).
  
  
  CONCLUSIONS
  The marked variations in EM risk among the five regions were partly related to differences in landscape and environmental characteristics. The latter may point out potential risk areas and provide information for targeting preventive actions.
authors.affiliation: 1 Institut de veille sanitaire, Département de Coordination des Alertes et Région, CIRE Bourgogne/Franche-Comté , Dijon, France .
authors.forename: Anne-Sophie
authors.initials: AS
authors.lastname: Mariet
authors.forename: Olivier
authors.initials: O
authors.lastname: Retel
authors.forename: Hélène
authors.initials: H
authors.lastname: Avocat
authors.forename: Anne
authors.initials: A
authors.lastname: Serre
authors.forename: Lucie
authors.initials: L
authors.lastname: Schapman
authors.forename: Marielle
authors.initials: M
authors.lastname: Schmitt
authors.forename: Martine
authors.initials: M
authors.lastname: Charron
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Monnet
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D002648:Child; D002675:Child, Preschool; D004463:Ecology; D004777:Environment; D005260:Female; D005602:France / Q000453:epidemiology; D005929:Glossitis, Benign Migratory / Q000453:epidemiology* / Q000517:prevention & control; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012737:Sex Factors; D055815:Young Adult